| A | B |
|---|
| chemical property | the ability of a substance to undergo a chemical reaction to form new substances |
| chemical reaction | the changing of substances to other substances by breaking old bonds and forming new ones |
| gas | matter that has no definite shape or volume, it adapts to the shape of container |
| heterogeneous | a mixture that is not uniform in composition, components are readily distinguishable |
| homogeneous | mixture that is completely uniform in composition, components not distinguishable |
| liquid | form of matter that flows has a fixed volume and takes the shape of the container |
| physical change | an alteration of a substance that does not affect its chemical composition |
| physical property | quality of a substance that can be observed or measured without changing its chemical composition |
| solid | matter which has a definite shape and volume |
| density | the ratio of the mass of an object to its density |
| significant figures | all the digits that can be known precisely in a measurement plus a last estimated digit |
| weight | a measure of the force of attraction between the earth and an object |
| mass | the amount of matter that an object contains the SI base unit of mass is a kilogram |
| atom | the smallest particle of an element that retains the properties of an element |
| atomic mass | the weighted average of the masses of the element |
| atomic number | the number of protons in the nucleus of an atom of an element |
| electron | negativly charged subatomic particle |
| isotope | atom of the same element that have the same atomic# but different atomic masses due to a different # of neutrons |
| mass number | total number of protons and neutrons in the nucleus of an atom |
| neutron | subatomic particle with no charge and a mass of one amu found in the nucleus of an atom |
| nucleus | dense central portion of an atom composed of protons and neutrons |
| proton | positively charged subatomic particle found in the nucleus of an atom |
| covalent atomic radius | half of the distance between the nuclei of two atoms in a hominuclear diatomic molecule |
| ionization energy | the energy required to remove an electron from a gaseous atom |
| period | a horizontal row of elements in the periodic table |
| group | vertical column of elements in the periodic table |
| physical property changes | color, solubility, mass, odor, density, melting point |
| chemical propery changes | color change, heating, producing a gas or solid, bubbles |
